The present invention relates to a shield assembly for highway signs supported on bridges, for deterring graffiti artists from defacing such signs.
Highway signs are often supported on bridges passing over public highways such as freeways and other roads. Such signs are positioned in a direction facing oncoming traffic. Bridge-supported highway signs are often defaced by graffiti artists, who lean over the bridge side wall or railing and spray messages with paint onto the signs. The sign must then be cleaned by city or transport authorities, and will often be defaced again after cleaning. The cost borne by transport authorities in cleaning graffiti from highway signs is enormous, and repeated cleaning of such signs is extremely time-consuming.